This application relates to retractable fall arrest units or blocks, and, in particular to an improved nozzle for the retractable fall arrest.
Retractable fall arrest units have been used for many years and range in size from small (6 ft.) units to large (175 ft.) units. The purpose of a retractable fall arrest unit is to allow workers who must work on the leading edge of elevated surfaces (or other areas where falls are of concern) to have a means to attach to an anchorage that will arrest their motion in case of an accidental fall. These retractables are usually equipped with a 3/16″ wire rope cable or a 1″ webbing lanyard of sufficient strength to withstand the forces from a fall (currently, at least 3600 lbs. of anchorage strength). The retractables are equipped with shock absorbers that will limit the forces of a falling worker to 900 lbs. or less during a fall arrest. These shock absorbers may comprise an internal mechanical clutch type or an external rip-stop type made of webbing.
A retractable fall arrest unit with a prior art nozzle is shown in FIG. 1. As seen, the retractable fall arrest unit 10 includes a housing 12 with an axle 14 that supports a cable drum 16, a braking assembly 18, and a spring assembly 20. A cable 22 is wound on the drum 16 and exits the housing through a nozzle 24. As is known, the housing can be secured to an anchor and the cable can be attached to a harness worn by a worker. As the worker moves about, the cable 22 will be pulled from and retracted into the housing as the worker's distance from the housing varies. Should the worker fall, the brake assembly 18 will slow and stop the worker's fall to reduce injury to the worker.
The standard or prior art nozzle 24 is a generally circular nozzle having a generally cylindrical outer surface and an inner surface which is generally hour-glass shaped. The inner surface thus defines an upper or inner portion 24a (within the retractable housing) which is generally conical and a lower or outer portion 24b, which is also generally conical. The two conical portions are joined at their apexes by a through bore 24c through which the cable extends. With this “standard” nozzle configuration, the cable has a tendency to wrap in the center of the drum due to the short fleet angle of a side retractable unit and will not fill all the way to the sides of the drum. This results in a build-up of cable in the center of the drum which can cause the cable to rub on the inner diameter of the housing and can prevent the full cable length from being able to retract on the drum even though the drum was large enough in depth and width to hold all the cable. It would be beneficial to provide a nozzle which reduced the possibility of this from occurring.